This invention relates to apparatus useful for adjusting the tenter rails so as to avoid excessive angles at the junctures between rails thus avoiding damage to the chains and rails. When changing cloth styles and widths, it is necessary to make transverse adjustments to the rails of a tenter frame in order to accommodate the changes. This operation may take place several times a day on cloth tenter frame rails where the tendency is to make shorter runs of cloth than heretofore. It has been found that the transverse adjusting screw activating mechanism may be driven excessively placing the rails at an angle such that damage is done to the tenter chains or other related mechanisms. While the invention has been described in connection with a textile tenter, this device would be useful in connection with a film tenter where adjustments are made for purposes of servicing chains adjusting for different film widths.
Accordingly, it is an object of this invention to provide an apparatus for limiting the angle of tenter frame rails utilizing a spring biased plunger carried on one side of a rail junction with an opposed member having a predetermined surface sufficient to support the spring biased plunger during normal movements of the rails which permits dislodgement of the spring biased plunger during excessive transverse movements of rails to signal a cessation of the rail driving mechanism or a warning system for a manually driven system.
Another important object of the invention is the provision of a rotatable cylindrical surface maintaining the plunger of a spring biased valve closed to flow during normal movement of tenter frame rails, but permitting dislodgement of the plunger therefrom when such movement is excessive in order to cause cessation of further excessive movement to the rails.